SCD-1, SCD-777ES - Sony Audio Service Manual (repair manual). Page 14

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Playback operations will start after the following nine procedures have been completed.

Rotates the spindle motor, rotating the disc at constant speed.

Sets laser power in accordance with disc type and outputs the laser from the optical block.

Table 3-1. Laser Power Settings

Disc Type

Optical Block

Laser Power

CD

CD

Regular

Hybrid (CD)

CD

Regular

SL

SACD

Low

DL

SACD

High

Hybrid (HD)

SACD

High

Conducts focus search operation and turns the focus servo ON.

Automatically adjusts the traverse signal from the TE signal and VC voltage. The automatically adjusted value will be stored until the disc

is replaced.

Turns servo operations ON and makes disc signals readable. Turns the tilt servo on for SACD playback only.

Automatically adjusts the focus bias from the RF jitter. The adjusted value will be stored until the disc is replaced.

Automatically adjusts the focus, tracking and all other gain values. Adjusted values are stored until the disc is replaced.

When playing SACDs, an invisible watermark signal will be detected and the disc’s validity confirmed.
The RF signal output from the RF amp’s SIGO terminal (Pin tj of IC001) is input to the A/D converter (Pin wl of IC708) via the RF

buffer (IC721), switch (IC739), and RF amp (IC722) and converted to an 8-bit digital value. This digital value is input to the DSD decoder
(IC703) and decoded inside it, confirming the validity of the invisible watermark.
When the invisible watermark detection operation has terminated, TOC information will be read and the disc type confirmed.

The disc’s TOC information will be read. If it is judged from the TOC information obtained and the result of invisible watermark detection

that the disc cannot be played, “TOC ERROR” will be displayed.

It is possible to determine whether a disc is an SACD or a DVD from the TOC information. As for DVDs, when a type of disc that cannot

be played is loaded, “TOC ERROR*” will be displayed.

Even when TOC information from an SACD is obtained, if the invisible watermark cannot be read, “TOC ERROR****” will be dis-

played. Please note that different numbers of “*” have different meanings.

Table 3-2. “TOC ERROR” Displays

Display

Disc Type

TOC ERROR*

Type that can’t be played (DVD, etc.)

TOC ERROR****

Illegal disc (pirated disc, etc.)

“TOC ERROR” will not be displayed for CD-ROMs (video CDs), but sound will not be output even if playback operations start.